2622-63-1Relevant articles and documents
Unexpected Roles of Triethanolamine in the Photochemical Reduction of CO2 to Formate by Ruthenium Complexes
Sampaio, Renato N.,Grills, David C.,Polyansky, Dmitry E.,Szalda, David J.,Fujita, Etsuko
, p. 2413 - 2428 (2020)
A series of 4,4′-dimethyl-2,2′-bipyridyl ruthenium complexes with carbonyl ligands were prepared and studied using a combination of electrochemical and spectroscopic methods with infrared detection to provide structural information on reaction intermediates in the photochemical reduction of CO2 to formate in acetonitrile (CH3CN). An unsaturated 5-coordinate intermediate was characterized, and the hydride-transfer step to CO2 from a singly reduced metal-hydride complex was observed with kinetic resolution. While triethanolamine (TEOA) was expected to act as a proton acceptor to ensure the sacrificial behavior of 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole as an electron donor, time-resolved infrared measurements revealed that about 90% of the photogenerated one-electron reduced complexes undergo unproductive back electron transfer. Furthermore, TEOA showed the ability to capture CO2 from CH3CN solutions to form a zwitterionic alkylcarbonate adduct and was actively engaged in key catalytic steps such as metal-hydride formation, hydride transfer to CO2 to form the bound formate intermediate, and dissociation of formate ion product. Collectively, the data provide an overview of the transient intermediates of Ru(II) carbonyl complexes and emphasize the importance of considering the participation of TEOA when investigating and proposing catalytic pathways.
Solvent-free rhodium(III)-catalyzed synthesis of 2-aminoanilides via C?H amidation of N-nitrosoanilines under ball-milling conditions
Li, Liang,Wang, Guan-Wu
, p. 4188 - 4196 (2018)
A solvent-free rhodium(III)-catalyzed C?H amidation of N-nitrosoanilines with 1,4,2-dioxazol-5-ones has been successfully developed under ball-milling conditions. This protocol provides an efficient and green access to a variety of 2-aminoanilide derivatives with low catalyst loading, remarkable functional group compatibility and excellent yields. In addition, the products allow convenient access to pharmaceutically valuable benzimidazole derivatives through a one-pot two-step synthesis.
Bimetallic Cooperative Catalysis for Decarbonylative Heteroarylation of Carboxylic Acids via C-O/C-H Coupling
Liu, Chengwei,Ji, Chong-Lei,Zhou, Tongliang,Hong, Xin,Szostak, Michal
supporting information, p. 10690 - 10699 (2021/04/09)
Cooperative bimetallic catalysis is a fundamental approach in modern synthetic chemistry. We report bimetallic cooperative catalysis for the direct decarbonylative heteroarylation of ubiquitous carboxylic acids via acyl C-O/C-H coupling. This novel catalytic system exploits the cooperative action of a copper catalyst and a palladium catalyst in decarbonylation, which enables highly chemoselective synthesis of important heterobiaryl motifs through the coupling of carboxylic acids with heteroarenes in the absence of prefunctionalization or directing groups. This cooperative decarbonylative method uses common carboxylic acids and shows a remarkably broad substrate scope (>70 examples), including late-stage modification of pharmaceuticals and streamlined synthesis of bioactive agents. Extensive mechanistic and computational studies were conducted to gain insight into the mechanism of the reaction. The key step involves intersection of the two catalytic cycles via transmetallation of the copper–aryl species with the palladium(II) intermediate generated by oxidative addition/decarbonylation.
Palladium-catalyzed hydrodefluorination of fluoroarenes
Brodney, Michael A.,Gair, Joseph J.,Giroux, Simon,Grey, Ronald L.
, p. 131 - 146 (2021/06/18)
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